Touch screen and manufacturing method thereof

ABSTRACT

The present invention provides a method of manufacturing a touch screen, comprising the steps of: a) forming a conductive layer on a substrate; b) forming an etching resist pattern on the conductive layer; and c) forming a conductive pattern having a line width smaller than the line width of the etching resist pattern by over-etching the conductive layer by using the etching resist pattern and a touch screen manufactured by the method. According to the present invention, a touch screen comprising a conductive pattern having an ultrafine line width can be economically and efficiently provided.

This application is a national stage application of PCT/KR/2010/000762,filed Feb. 8, 2010, which claims priority from Korean Patent ApplicationNos. 10-2009-0009750, 10-2009-0065103, 10-2009-0065106, and10-2009-0127756, filed on Feb. 6, 2009, Jul. 16, 2009, Jul. 16, 2009,and Dec. 21, 2009 in the Korean Intellectual Property Office,respectively, all of which are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

The present invention relates to a touch screen and a manufacturingmethod thereof.

BACKGROUND ART

In general, a touch screen is used by patterning an ITO-based conductivelayer, but when the ITO is applied to a large-area touch screen, arecognition speed lowers due to self-RC relay. In order to solve theproblem, a technology for displacing the ITO by using a printing methodhas been developed in a lot of corporations, but the technology isdifficult to form a fine pattern having high accuracy which is invisibleto the naked eye with respect to visibility.

DISCLOSURE Technical Problem

In order to solve problems in the related art, the present inventionprovides a manufacturing method capable of economically and efficientlymanufacturing a touch screen comprising a conductive pattern having highaccuracy and an ultrafine line width and a touch screen manufactured bythe method.

Technical Solution

An exemplary embodiment of the present invention provides a method ofmanufacturing a touch screen, comprising the steps of: a) forming aconductive layer on a substrate; b) forming an etching resist pattern onthe conductive layer; and c) forming a first conductive pattern having aline width smaller than the line width of the etching resist pattern byover-etching the conductive layer by using the etching resist pattern.

The method of manufacturing a touch screen according to the presentinvention may further comprise d1) forming a second conductive patternin the same manner as steps a) to c), except for forming on theconductive layer on not the substrate but the first conductive pattern,d2) forming a second conductive pattern on the substrate in the samemanner as steps a) to c) at an opposite side of a surface formed withthe first conductive pattern of the substrate, or d3) laminating asurface of the substrate with a second conductive pattern on a surfaceof the substrate with the first conductive pattern or a surface with thefirst conductive pattern after forming the second conductive pattern onan additional substrate in the same manner as steps a) to c).

The method may further comprise e) removing the etching resist pattern;or f) reforming the etching resist pattern so as to cover the conductivepattern, after step c). The method may further comprise forming aninsulating layer on the first conductive pattern, when performing stepe).

In steps d1) to d3), an additional insulating layer may be formed on thesecond conductive pattern after forming the second conductive pattern inthe same manner as steps a) to c).

Another exemplary embodiment of the present invention provides a touchscreen comprising: a substrate; a conductive pattern formed on at leastone side of the substrate; and an insulating layer pattern covering theconductive pattern and manufactured by using the method of manufacturingthe touch screen.

Another exemplary embodiment of the present invention provides a touchscreen comprising: a substrate; a conductive pattern formed on at leastone side of the substrate; and an insulating layer pattern covering theconductive pattern, in which a taper angle of the conductive pattern issmall. The conductive pattern may have a taper angle of more than 0 toless than 90 degrees, preferably, more than 0 to 45 degrees or less, andmore preferably, more than 0 to 30 degrees or less.

Another exemplary embodiment of the present invention provides a touchscreen comprising: a substrate; a conductive pattern formed on at leastone side of the substrate; and an insulating layer pattern covering theconductive pattern, in which a taper angle of the insulating layerpattern is small. The insulating layer pattern may have a taper angle ofmore than 0 to less than 90 degrees, preferably, more than 0 to 70degrees or less, and more preferably, more than 0 to 30 degrees or less.

Another exemplary embodiment of the present invention provides a touchscreen comprising: a substrate; a conductive pattern formed on at leastone side of the substrate; and an insulating layer pattern covering theconductive pattern, in which a taper angle of the insulating layerpattern is larger than the taper angle of the conductive pattern. Thetaper angle of the insulating layer pattern is not particularly limitedif being larger than that of the conductive pattern, but more preferablylarger than that of the conductive pattern by more than 0 degree and 4degrees or less.

Another exemplary embodiment of the present invention provides a touchscreen comprising: a substrate; a conductive pattern formed on at leastone side of the substrate; and an insulating layer pattern covering theconductive pattern, in which a void is comprised between the conductivepattern and the insulating layer pattern.

Another exemplary embodiment of the present invention provides a touchscreen comprising: a substrate; and a conductive pattern formed on atleast one side of the substrate and having a line width of 100micrometers or less, preferably, 0.1 to 30 micrometers, more preferably,0.5 to 10 micrometers, and more preferably, 1 to 5 micrometers. Thetouch screen according to the exemplary embodiment may further comprisean insulating layer pattern covering the conductive pattern on theconductive pattern. The touch screen may further comprise an insulatinglayer pattern having a pattern corresponding to the conductive patternand a line width larger than the line width of the conductive pattern.

Another exemplary embodiment of the present invention provides a touchscreen comprising: a substrate; a conductive pattern formed on at leastone side of the substrate; and an insulating layer pattern covering theconductive pattern or an insulating layer pattern having a patterncorresponding to the conductive pattern and a line width larger than theline width of the conductive pattern, in which in a cross-section of theline width direction of the conductive pattern, a percentage a/b*100 ofa distance a from one end of the conductive pattern to the insulatinglayer pattern and a distance b from the other end of the conductivepattern to the insulating layer pattern is in the range of 90 to 110.

Advantageous Effects

According to exemplary embodiments of the present invention, since atouch screen can comprise a conductive pattern with high precision andan ultrafine line width, the touch screen is excellent in performanceand very efficient and economic in manufacturing method thereof.Further, the conductive pattern is in high precision and has theultrafine line width and in addition, can have a large area.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1 to 5 are exemplified diagrams illustrating exemplary embodimentsof a method according to the present invention.

FIG. 6 is a photograph illustrating a line width of a conductive patternaccording to over-etching degree.

FIG. 7 is a photograph illustrating the case where an etching resistpattern comprises a remaining region and an area having differenthardness in a touch screen according to an exemplary embodiment of thepresent invention.

FIGS. 8 to 11 are exemplified diagrams illustrating a structure in whichan etching resist pattern having a line width larger than a line widthof the conductive pattern is provided on the conductive pattern.

FIGS. 12 to 15 are exemplified diagrams illustrating an insulating layerpattern which is disposed in a symmetric structure with respect to theconductive pattern.

FIG. 16 is a schematic diagram illustrating an effect in that a cause ofa short generation can be removed by using a method according to thepresent invention.

FIGS. 17 to 19 are exemplified diagrams illustrating a side structure ofa touch screen according to an exemplary embodiment of the presentinvention.

FIGS. 20 to 21 are exemplified diagrams illustrating a method ofmanufacturing a touch screen according to an exemplary embodiment of thepresent invention.

FIGS. 22 to 23 are exemplified diagrams illustrating a state in which aconductive pattern is divided in a touch screen according to anexemplary embodiment of the present invention.

FIGS. 24 to 25 are exemplified diagrams illustrating a structure inwhich a touch screen according to an exemplary embodiment of the presentinvention is connected to external voltage.

FIGS. 26 to 29 are exemplified diagrams illustrating a conductivepattern of a touch screen according to an exemplary embodiment of thepresent invention.

FIG. 30 is an exemplified diagram illustrating a pattern formation usinga Voronoi diagram generator.

FIGS. 31 to 33 are exemplified diagrams illustrating a conductivepattern of a touch screen according to an exemplary embodiment of thepresent invention.

FIG. 34 is a diagram illustrating a forming example of a Delaunaypattern.

FIGS. 35 to 37 are exemplified diagrams illustrating a Delaunay pattern.

FIGS. 38 to 39 are exemplified diagrams illustrating a result ofevaluating visibility in the case where a mesh shape of conductivepattern is divided and in the case where a conductive wire is put on amesh shape of conductive pattern.

FIG. 40 is an exemplified diagram illustrating a moiré effect accordingto a line width and a pitch.

FIGS. 41 to 43 are diagrams illustrating a conductive patternmanufactured in Example 1.

FIG. 44 is a diagram illustrating a conductive pattern manufactured inExample 2.

FIG. 45 is an exemplified diagram illustrating a method of generatingirregular and uniform reference points in order to form a conductivepattern.

BEST MODE

Hereinafter, the present invention will be described in more detail.

A method of manufacturing a touch screen according to the presentinvention comprises the steps of a) forming a conductive layer on asubstrate; b) forming an etching resist pattern on the conductive layer;and c) forming a first conductive pattern having a line width smallerthan a line width of the etching resist pattern by over-etching theconductive layer by using the etching resist pattern. In thisspecification, the over-etching is to etch the conductive layer so as tohave a line width smaller than a line width of the etching resistpattern.

In the case where the touch screen according to the present inventioncomprises two or more conductive patterns, the method of manufacturingthe touch screen according to the present invention may further compriseany one of the following steps d1) to d3):

d1) forming a second conductive pattern in the same manner as steps a)to c), except for forming on the conductive layer on not the substratebut the first conductive pattern;

d2) forming a second conductive pattern on the substrate in the samemanner as steps a) to c) at an opposite side of a surface formed withthe first conductive pattern of the substrate; or

d3) laminating a surface of the substrate with a second conductivepattern on a surface of the substrate with the first conductive patternor a surface with the first conductive pattern after forming the secondconductive pattern on an additional substrate in the same manner assteps a) to c).

In this specification, a method or a material of forming a conductivepattern to be described below may be applied to the first conductivepattern and the second conductive pattern.

The manufacturing method may further comprise e) removing the etchingresist pattern; or f) reforming the etching resist pattern so as tocover the conductive pattern, after step c). In the case of performingstep e), the method may further comprise forming an insulating layer onthe first conductive pattern. An example using step e) is shown in FIGS.1 and 3 and an example using step f) is shown in FIGS. 2 and 4, but thescope of the present invention is not limited to the processes shown inthe drawings and some processes shown in FIGS. 1 to 4 may be omitted oradded, if necessary.

In step d), an additional insulating layer may be formed on the secondconductive pattern after forming the second conductive pattern in thesame manner as steps a) to c).

In this specification, when the etching resist pattern has an insulatingproperty, the description for the insulating layer pattern may beapplied.

The material of the substrate may be properly selected according to afield to intend to apply the method of manufacturing the conductivepattern according to the present invention and a preferable example is aglass or inorganic material substrate, a plastic substrate, or otherflexible substrates, but the material of the substrate is not limitedthereto.

In addition, the material of the conductive layer is not particularlylimited, but may be a metal layer. A particular example of the materialof the conductive layer may be a single layer of a multilayer comprisingsilver, aluminum, copper, neodium, molybdenum or an alloy thereof.Herein, a thickness of the conductive layer is not particularly limited,but may be 0.01 to 10 μm with respect to conductivity of the conductivelayer and economical efficiency of a forming process.

The method of forming the conductive layer is not particularly limited,but may use a method such as deposition, sputtering, wet coating,evaporation, electrolytic plating or electroless plating, lamination ofa metal foil, or the like. According to the method of the presentinvention, the conductive pattern comprised in an effective screen partof electronic components for a display and a wire part for applying asignal thereof can be formed at the same time. Particularly, the methodof forming the conductive layer may use a method for grantingconductivity by firing and/or drying after coating a solution comprisingorganic metal, nano-metal, or a complex thereof on the substrate. Theorganic metal may use organic silver and the nano-metal may usenano-silver particles or the like.

In the present invention, the method may further comprise forming abuffer layer for improving adhesivity on the substrate, before formingthe conductive layer.

The method according to the present invention may further comprisewashing the formed conductive layer after step a).

The inventors of the present invention found that a line edge roughness(LER) of the etch resist pattern formed in step b) determines a criticaldimension of a minimum line width of the conductive pattern which can beformed by the over-etching without disconnection. When the line edgeroughness (LER) of the etch resist pattern is very large, the conductivepattern may be disconnected before acquiring the conductive patternhaving a desired line width in the over-etching. The line edge roughness(LER) of the etching resist pattern may be a half of the minimum linewidth of the conductive pattern. Accordingly, the line edge roughness(LER) of the etching resist pattern may be controlled by a half of aline width of the desired conductive pattern. Therefore, the line edgeroughness (LER) of the etching resist pattern is preferably 0.1 to 5micrometers, and more preferably, 0.2 to 5 micrometers. In the case ofthe range, it is advantageous to form the conductive pattern having anultrafine line width of 10 micrometers or less, and preferably, 5micrometers or less. Herein, the line edge roughness (LER) means aheight of the most protruding point based on the deepest point in theline edge of the etching resist pattern.

In step b), a method of forming the etching resist pattern is preferablya printing method, a photolithography method, a photography method, amethod using a mask, or a laser transfer, for example, thermal transferimaging method and more preferably, the printing method or thephotolithography method.

The printing method may be performed by transferring and firing a pasteor an ink comprising an etching resist material on the substrate formedwith the conductive layer in a desired pattern form. The transferringmethod is not particularly limited, but may be performed by forming thepattern on a pattern transfer medium such as an intaglio or a screen andtransferring the desired pattern on the conductive layer by using thesame. The method of forming the pattern form on the pattern transfermedium may use a known method in the art.

The printing method is not particularly limited, but may use a printingmethod such as a gravure offset printing, a reverse offset printing, ascreen printing, a gravure printing and more preferably, the gravureoffset printing or the reverse offset printing method in order toacquire the conductive pattern having an ultrafine line width by formingthe etching resist pattern within the range of the line edge roughness(LER) described above.

The reverse offset printing method may be performed by forming a desiredpattern on a blanket by applying a paste on a roll-type blanket andthen, contacting the paste with a cliché having unevenness, andthereafter, transferring the pattern formed on the blanket to theconductive layer. The print method was shown in FIGS. 1 and 2. Inaddition, the gravure offset printing method may be performed by fillinga paste into an intaglio having a pattern, primary transferring thepaste with silicon rubber called a blanket, and secondary transferringby contacting the blanket and the substrate formed with the conductivelayer. The printing method was shown in FIGS. 3 to 5. However, themethod of implementing the present invention is exemplified in FIGS. 1to 5 and the scope of the present invention is not limited thereto. Someprocesses shown in FIGS. 1 to 5 may be omitted or added, if necessary.

In the case of the gravure offset printing method or the reverse offsetprinting method, since the ink or the paste is almost transferred on thesubstrate with the conductive layer due to releasing property of theblanket, washing for the blanket is not additionally needed. Theintaglio may be manufactured by etching precisely the substrate. Theintaglio may be manufactured by etching a metal plate or may bemanufactured by optical patterning using a polymer resin.

The screen printing method may be performed by positioning a paste on ascreen having a pattern and then, directly positioning the paste on thesubstrate with the conductive layer through the screen having an emptyspace while pushing a squeeze. The gravure printing method may beperformed by winding the blanket having the pattern on a roll, fillingthe paste into the pattern, and then, transferring the paste on thesubstrate with the conductive layer. In the present invention, themethods may be singly used and may be complexly used. In addition, otherprinting methods which are known to a person with ordinary skill in theart may be used.

In the present invention, the printing methods may be used andparticularly, the offset printing method, the reverse offset printingmethod, or the gravure printing method may be used.

In the case of the reverse offset printing method, a viscosity on an inkfor printing comprising the material of the etching resist pattern ispreferably more than 0 cps to 1000 cps or less and more preferably 5 cpsto 10 cps. In addition, in the case of the gravure printing method, aviscosity of the ink is preferably 6,000 cps to 12,000 cps, and morepreferably 7,000 cps to 8,000 cps. When the viscosity of the ink iswithin the range, in each printing method, the coating of the ink can beperformed well and stability of the ink in the process (processmaintaining capability of the ink) can be maintained.

In the present invention, the method of forming the etching resistpattern is not limited to the printing methods described above and mayuse the photolithography method. For example, the method may beperformed by forming a etching resist layer having photosensitivity andacid resistance (resistance for etching) on the conductive layer andpatterning the formed etching resist layer by selective exposure anddevelopment.

In the case of reforming the etching resist pattern so as to cover theconductive pattern after etching the conductive layer by using theetching resist pattern as a mask, a taper angle of the etching resistpattern is preferably more than 0 to less than 90 degrees and morepreferably 10 or more to 70 degrees or less. When the taper angle of theetching resist pattern is within the range, the etching resist patternmay be easily reformed and the etching resist pattern may sufficientlycover the conductive pattern.

The etching resist pattern is preferably formed by using a materialhaving acid resistance and sufficient adhesion with the conductive layerwithout reacting with an etchant used in the etching of the conductivelayer. In addition, in the case of reforming the etching resist patternso as to cover the conductive pattern after etching the conductive layerby using the etching resist pattern as a mask, the material of theetching resist pattern may have insulating property. Further, in stepf), the material of the etching resist pattern preferably use a polymermaterial having mobility and acid resistance by processing under acondition used in the reformation of the etching resist pattern, forexample, heat, solvent, fume (fume of the solvent), plasma, or the like,and more preferably use a polymer material having a cross-linkingproperty.

The material of the etching resist pattern may have insulation with aleakage current of 10⁻¹ ampere or less. The leakage current of thematerial of the etching resist pattern may be 10⁻¹⁶ ampere or more. Thematerial of the etching resist pattern preferably has acid resistancefor the etchant of the conductive layer used in the corresponding methodand for example, is preferably a material without a change in a shapefor 10 minutes when contacting the etchant of the correspondingconductive layer by an immersing or spraying method.

Further, the material of the etching resist pattern preferably hasmobility under a processing condition for step f) to be described below.In particular, the material of the etching resist pattern may use apolymer material having plasticity and curability. In the presentinvention, the material of the etching resist pattern may use athermosetting resin and a UV curable resin. The UV curable resin may notuse a solvent as compared with the thermosetting resin, such that thereis no problem due to the evaporation of the solvent and a stable shapeof fine pattern is advantageously formed. FIG. 5 exemplifies the case ofmanufacturing the etching resist pattern by using the UV curable resin.

In detail, the material of the etching resist pattern may use, forexample, imide-based polymer, bisphenol-based polymer, epoxy-basedpolymer, acryl-based polymer, ester-based polymer, novolac-basedpolymer, or a combination thereof. Among the polymers, the acryl-based,imide-based, or novolac-based polymer resin is preferably used. Inaddition, the material of the etching resist pattern may use two or morecombinations or copolymer of imide-based monomer, bisphenol-basedmonomer, epoxy-based monomer, acryl-based monomer, and ester-basedmonomer and for example, copolymer of epoxy and acryl resin or epoxy andacryl monomer may be used.

In the case of the etching resist pattern formed by the printing method,process margin can be increased by controlling a content of solid orproperly selecting a solvent.

The content of the solid in an ink composition for forming the etchingresist pattern may be differently controlled according to a kind of theprinting methods or a thickness of the etching resist pattern. Forexample, in the case of the gravure offset printing method, the contentof the solid of the etching resist pattern composition is preferably 70to 80 wt %. Further, in the case of forming the etching resist patternhaving a thickness of 100 nm to 10 micrometers, and more preferably 500nm to 2 micrometers by using the reverse offset printing method, thecontent of the solid of the etching resist pattern composition ispreferably 10 to 25 wt %. However, the scope of the present invention isnot limited to the examples and the content of the solid of the etchingresist pattern composition can be controlled by the person with ordinaryskill in the art according to other materials or process conditions.

A solvent that can be added in the etching resist pattern compositionmay use a solvent used in the art and may use a single kind or two ormore kinds of mixed solvent. For example, any solvent which does notcause damage to a blanket material used in the printing method, forexample, PDMS is not particularly limited. For example, propylene glycolmethyl ether acetate (PGMEA), ethanol, propylene carbonate, butylcellosolve, dimethyl acetamide (DMAc), methyl ethyl ketone (MEK), methylisobutyl ketone (MIBK), or the like may be used.

The composition for forming the etching resist pattern may furthercomprise an adhesion promoter, a surfactant, and the like.

In the case of reforming the etching resist pattern so as to cover theconductive pattern after etching the conductive layer by using theetching resist pattern as a mask, in order to sufficiently cover aconductive wire with the etching resist pattern, a thickness of theetching resist pattern is preferably larger than a thickness of theconductive wire, but is not limited thereto. In addition, a width of theetching resist pattern may be properly selected by the person withordinary skill in the art according to a field to which the method ofthe present invention is applied, but is not particularly limited. Forexample, a lower width of the etching resist pattern preferably has adimension so as to cover both an upper surface and a side surface of theconductive wire.

In step c), the conductive pattern is formed so as to have a line widthsmaller than the line width of the etching resist pattern byover-etching by using the etching resist pattern as the mask.

The etching method may be a wet-etching using an etchant or adry-etching using plasma or a laser, but is not limited thereto.

In the wet-etching, the etchant may be a nitric acid solution, a mixedacid solution of phosphate/nitrate/acetate, one or two or more of anitric acid (HNO₃) solution, a mixed acid solution of phosphoricacid/nitric acid/acetic acid, hydrogen peroxide, perchloric acid,hydrochloric acid, hydrofluoric acid, and oxalic acid, or an aqueoussolution thereof may be used as the etching solution, and if necessary,an additive and other elements for etching the desired conductive layermay be added thereto, but the solution is not limited thereto. Ingeneral, an etchant known as an etching solution of the correspondingconductive layer may be used.

In step c), when etching the conductive layer, an undercut is formed atthe lower portion of an edge of the etching resist pattern by performingthe over-etching.

The “undercut” means a shape having an area of a first layer smallerthan an area of a second layer by being over-etched at the side of thefirst layer, when only the first layer is selectively etched by usingthe second layer as a mask after forming the first layer on thesubstrate and the second layer thereon. Herein, “by using the secondlayer as a mask” means that the second layer is not deformed or removedby the etching and is left as it is.

In the general etching process, when the first layer is etched by usingthe second layer as a mask, a pattern of the first layer is implementedin the same shape as a pattern of the second layer and the formation ofthe undercut is prevented.

However, in the present invention, the conductive pattern having a linewidth further thinner than a line width of the etching resist patternmay be acquired by etching the conductive layer so as to form theundercut at the lower portion of the etching resist pattern.

In step c), when the undercut is formed by the over-etching, a linewidth or a length of the etching resist pattern is larger than a linewidth or a length of the conductive pattern.

Further, when the undercut is generated, a taper angle of the conductivepattern is more than 0 to less than 90 degrees, more preferably morethan 0 to 45 degrees or less, and more preferably more than 0 to 30degrees or less, but is not limited thereto. Herein, the taper anglemeans an angle between an end of the conductive pattern and a lowerlayer thereof, that is, a surface of the substrate. The taper angle maybe measured by an angle between a straight line having an average slopeof tangents from an end point of the conductive pattern to a point atwhich an upper surface of the conductive pattern start to be flat and alower layer surface thereof. In the present invention, the conductivepattern having a small taper angle may be provided by using the methodunlike the related art.

In step c), the line width of the conductive pattern may be controlledaccording to an etching time for forming the conductive pattern. As theetching time is longer, the line width of the conductive pattern may bethinly formed.

In the present invention, the etching time for forming the conductivepattern may vary according to a condition such as a kind orconcentration of etchant used in the formation of the conductivepattern, a kind of conductive layer, an etching temperature, and thelike. For example, the etching time is a just-etching time to a timemore extended by 2,000% than the just-etching time, preferably a timemore extended by 1 to 1,000% than the just-etching time, more preferablya time more extended by 1 to 500% than the just-etching time, andfurther more preferably a time more extended by 5 to 100% than thejust-etching time. Herein, the just-etching time means a time requiredwhen a pattern is etched in the same shape as the shape of the mask. Theline width of the conductive pattern according to the etching time wasshown in FIG. 6.

The etching temperature of the conductive layer may also vary accordingto a condition such as a kind or concentration of etchant used in thepatterning of the conductive layer, a kind of conductive layer, anetching temperature, and the like and for example, may be roomtemperature to 80 degrees, and preferably 30 to 70 degrees.

The etching method may be a deep etching method, a spray method, or thelike, but more preferably the spray method for uniform etching.

When the conductive layer is a multilayer film, an etchant for etchingthe multilayer film at the same time and at almost the same speed may beused.

After etching the conductive layer by using the etching resist patternas a mask, the etching resist pattern may be removed like step e), butthe conductive layer without removing the etching resist pattern may beused to the touch screen as it is. Further, like step f), the conductivepattern may be covered by reforming the etching resist pattern.

In step e), the etching resist pattern may be removed by using a knownmethod in the art according to a kind of etching resist patternmaterial.

In step f), “covering” means that the etching resist pattern whichreflows while the shape is changed contacts the side of the conductivepattern and the substrate to insulate the conductive layer from theoutside. In addition, in the present invention, “reforming” defined inthe specification means that the etching resist pattern has mobility andthe shape thereof is changed to cover the conductive pattern disposed atthe lower portion.

In step f), the etching resist pattern may be reformed by modifying theetching resist pattern having the mobility by heat, solvent or fume(fume of the solvent), or plasma processing and then, curing the etchingresist pattern by an additional processing of heat or plasma or theremoval of the solvent, in which is a chemical processing. Or, apressure may be applied to the etching resist pattern to be physicallydeformed.

The etching resist pattern may be reformed by using heat or a solvent(or fume of the solvent) and in this case, the plastic or curablepolymer material may be used as the material of the etching resistpattern, as described above.

In the case of reforming the etching resist pattern by the heat, as theheat is applied, the material of the etching resist pattern has mobilityto sink to a space between the substrate and the etching resist patternand then, as the heat is further applied, the material is cured to lossthe mobility. In this case, the heating temperature may be properlyselected by the person with ordinary skill in the art according to thematerial of the etching resist pattern. The heating condition may becontrolled so that the etching resist pattern has a desiredcross-linking degree, for example, 10 to 100% or a desired insulatingproperty, for example, leakage current of 10⁻¹ ampere or less. Forexample, the heating may be performed at the temperature of 120° C. to350° C. to be increased by 5° C./min to 60° C./min. In addition, heatingof the same temperature or duplicate heating of different temperaturesmay be also performed. As a detail example, when the imide-based resinis used as the etching resist pattern material, the heating may beperformed at the temperature of 250° C. to 300° C. As another example,when the novolac-based resin is used as the etching resist patternmaterial, the heating may be performed at the temperature of 120° C. to140° C.

When the etching resist pattern is reformed by using the solvent or thefume of the solvent, the etching resist pattern may be exposed at theatmosphere of the fume of the solvent (solvent annealing). As a result,when the etching resist pattern material reacts with the solvent, theetching resist pattern material has mobility and the etching resistpattern is deformed to contact the substrate. Thereafter, when thesolvent is removed by heating at a predetermined temperature in whichthe solvent is dried, the etching resist pattern material is cured toloss the mobility. Such a reforming method is preferable. In this case,the solvent may be properly selected by the person with ordinary skillin the art according to the etching resist pattern material and may beselected from a solvent group in which the etching resist patternmaterial is soluble. For example, when the novolac-based resin is usedas the etching resist pattern material, IPA may be used as the solvent.Further, a dry temperature may be around a melting temperature of theselected solvent and preferably from room temperature to 300° C., but isnot limited thereto.

In the present invention, a baking process may be performed during orafter step b) of forming the etching resist pattern (FIGS. 1 to 4). Indetail, the baking process may be performed after forming the etchingresist pattern after forming the etching resist layer on the substrateduring step b), or before forming the conductive pattern in step c). Thebaking may be performed so as to prevent the modification of the etchingresist pattern in the baking step or subsequent steps by making theadhesion between the etching resist pattern and an adjacent layerthereto and simultaneously, at least partially curing the etching resistpattern and thereafter, stably form a reflowing shape of the etchingresist pattern in the reformation of the etching resist pattern, ifnecessary. The curability of the etching resist pattern desired to beaccomplished in the baking process may be determined by the person withordinary skill in the art according to the material of the etchingresist pattern or a condition for the reforming to be subsequentlyperformed, if necessary and for example, the curability may be in therange of 0 to 100%.

The condition of the baking process may be selected by the person withordinary skill in the art according to a material of the etching resistpattern, a thickness of the etching resist pattern, and an etchingcondition used to form the conductive wire, for example, a kind ofetchant, an etching time, an etching temperature, and the like. If thebaking temperature is very high, the cross-linking degree of the etchingresist pattern is very high, such that the modification, for example,distortion of a pattern area and the like may occur.

As one example, when the etching resist pattern is formed by usingnovolac-based polymer and the photolithography method, the baking may beperformed at the temperature of 80 to 150° C. for 2 to 3 minutes. Asanother example, when the etching resist pattern is formed by usingnovolac-based polymer and the printing method, the baking may beperformed at the temperature of 125 to 130° C. for 2 to 3 minutes. Asanother example, when the etching resist pattern is formed by usingacryl-based polymer, the baking may be performed at the temperature of170 to 230° C. for 5 to 60 minutes. As another example, when the etchingresist pattern is formed by using PSPI polymer, the baking may beperformed at the temperature of 120 to 300° C. for 1 to 60 minutes.

When the baking temperature is very low, it is difficult to acquire across-linking effect according to the baking and when the bakingtemperature is very high, the shape may be deformed due to thedistortion of the etching resist pattern. The baking time may varyaccording to the material or the process condition described above andfor example, may be about 2 to 3 minutes, but is not limited thereto.

In the present invention, when the UV curable resin is used as theetching resist pattern material, the exposure and the firing may beperformed during or after step b). The example was shown in FIG. 5.

The method according to the present invention may further comprisewashing after steps c), e), and f). The washing may be performed byusing the etchant used in step c). The washing may remove foreignsubstances.

The touch screen according to an exemplary embodiment of the presentinvention has a low taper angle of the conductive pattern and the taperangle is less than 90 degrees, preferably 45 degrees or less, and morepreferably 30 degrees or less.

In the present invention, when performing step f), in the touch screenaccording to the present invention, the etching resist pattern maycomprise a remaining region and a region having different hardnessdepending on a material of the etching resist pattern. The remainingregion and the region having different hardness may occur at aninterface of a region at which the etching resist pattern is notreformed and a region at which the etching resist pattern is reformedand may be formed in a band shape at the interface. The band may have anupwardly protruding shape compared with the rest regions in thecross-section. The band shape may be observed in FIG. 7.

In the present invention, by reforming the etching resist pattern, adistance between an end point of the conductive pattern and an end pointof the etching resist pattern may be controlled by 0 to 1 micrometer or5 micrometers or more. In particular, when the thermosetting resin isused as the etching resist pattern material, the distance between an endpoint of the conductive pattern and an end point of the etching resistpattern may be much shorter as 0 to 1 micrometer. Meanwhile, when athermosplastic resin is used as the etching resist pattern material, thedistance between an end point of the conductive pattern and an end pointof the etching resist pattern may be relatively long by 5 micrometers ormore.

In the present invention, when the etching resist pattern is reformed, avoid may be observed between the conductive pattern and the etchingresist pattern. This is different from the related art in which the voidis not observed when the insulating layer is formed on the conductivepattern. In the present invention, a thickness of the void (the shortestdistance between the longest side and the shortest side) is preferablyfrom more than 0 to a thickness of the conductive pattern or less andmore preferably more than 0 to 0.7 or less of the thickness of theconductive pattern.

In the touch screen according to an exemplary embodiment of the presentinvention, the taper angle of the reformed etching resist pattern may belarger than the taper angle of the conductive pattern.

In the touch screen manufactured by the method according to the presentinvention, a shape of a cross-section of the reformed etching resistpattern may be a semicircle.

In the touch screen according to an exemplary embodiment of the presentinvention, a line width of the conductive pattern is not particularlylimited, but the conductive pattern may have a fine line width of 100micrometers or less, preferably 0.1 to 30 micrometers, more preferably0.5 to 10 micrometers, and further more preferably 1 to 5 micrometers.In particular, in the described method, when etching the conductivelayer by using the etching resist pattern as a mask, more fine linewidth may be implemented by forming the undercut by the over-etching.

The touch screen according to the present invention may further comprisean insulating layer pattern disposed on the conductive pattern andcovering the conductive pattern or an etching resist pattern having apattern corresponding to the conductive pattern and having a line widthlarger than a line width of the conductive pattern. The insulating layerpattern covering the conductive pattern may have a structure as shown inFIGS. 12 and 13 and the etching resist pattern having a patterncorresponding to the conductive pattern and having a line width largerthan a line width of the conductive pattern may have a structure asshown in FIGS. 8 to 11. However, the scope of the present invention isnot limited by the drawings.

The structure may be manufactured without removing the etching resistpattern used as the mask for forming the conductive pattern, afterforming the conductive pattern by the described method. In this case,the etching resist pattern may have insulating properties.

When the etching resist pattern is formed on the conductive pattern, anoptical property can be additionally given by controlling a kind of theetching resist pattern material and a tri-dimensional shape thereof. Thestructure, in which the etching resist pattern having a line widthlarger than a line width of the conductive pattern is provided on theconductive pattern according to the present invention, was shown inFIGS. 8 to 11. However, it is not limited to only the structure shownthe drawings and may have other structures, and the etching resistpattern may be removed.

The touch screen according to an exemplary embodiment of the presentinvention comprises a substrate; a conductive pattern formed on at leastone side of the substrate; and an insulating layer pattern covering theconductive pattern or an insulating layer pattern having a patterncorresponding to the conductive pattern and a line width larger than theline width of the conductive pattern, in which in a cross-section of theline width direction of the conductive pattern, a percentage a/b*100 ofa distance a from one end of the conductive pattern to the insulatinglayer pattern and a distance b from the other end of the conductivepattern to the insulating layer pattern is in the range of 90 to 110.The percentage is preferably 95 to 105 and more preferably 99 to 101. Inthe method according to the present invention, the insulating layerpattern and the conductive pattern are not formed by using an additionalmask or an additional printing method, and the conductive pattern isformed by using the insulating layer pattern as a mask and thereafter,the insulating layer pattern is reformed to be used, such that theinsulating layer pattern disposed on the conductive pattern may besymmetric to the conductive pattern. The symmetric structure wasexemplified in FIGS. 12 to 15, but the scope of the present invention isnot limited to the structure.

According to the method of the present invention, although a patterndefect occurs at the time of the formation of the etching resist patternor the conductive pattern during the manufacturing process of the touchscreen, an insulated conductive pattern without the short may beprovided. Herein, the pattern defect means that the insulating patternfor forming the conductive pattern is formed at portions other than thepattern shape. In the present invention, the etching resist pattern usedto form the conductive pattern is not removed and the shape thereof isreformed, such that the etching resist pattern is used to insulate theconductive pattern. As a result, the conductive pattern which is notinsulated by the insulating pattern does not exist. Accordingly,although the pattern defect occurs at the time of the formation of theetching resist pattern or the conductive pattern, the foreign substancessuch as the conductive material are not left on the substrate, such thatthe short does not occur. In the related art, the conductive pattern isnot entirely covered due to the pattern defect of the insulating layerpattern or the conductive pattern which is not covered by the insulatinglayer pattern exists due to the pattern defect of the conductivepattern, such that the short may occur. On the other hand, in thepresent invention, an error rate may be largely reduced by the reasonsdescribed above and an additional washing or etching process forremoving the defect area of the conductive pattern, which is requiredfor the related art, may not be required. The effect of the presentinvention is shown in FIG. 16. Therefore, according to the method of thepresent invention, an insulated conductive pattern in which a shortcaused due to the defective pattern is not substantially occurred can beprovided.

The touch screen comprising the conductive pattern according to theexemplary embodiment of the present invention was exemplified in FIGS.17 and 18. FIG. 17 shows a structure in which the conductive pattern isprovided at one side of a single layer or a multilayer base and FIG. 18shows a structure in which the conductive pattern is provided at bothsides of a single layer or a multilayer base.

As one example of an electronic element according to an exemplaryembodiment of the present invention, a structure of the touch screen wasshown in FIG. 19. The touch screen shown in FIG. 19 comprises asubstrate, a first conductive pattern disposed on the substrate, a firstinsulating layer disposed on the first conductive pattern, a secondconductive pattern disposed on the first insulating layer, and a secondinsulating layer disposed on the second conductive pattern.

However, the scope of the present invention is not limited to FIGS. 17to 19.

The method of manufacturing the touch screen according to the presentinvention is exemplified in FIGS. 20 and 21. FIG. 20 shows an examplewhere a touch screen is manufactured by using a single substrate andFIG. 21 shows an example where a touch screen is manufactured by forminga conductive pattern and then, laminating the conductive pattern byusing two sheets of substrates.

The conductive pattern of the touch screen according to the presentinvention may be divided by a straight line and a curved line. Herein,the division means that the conductive pattern is disconnected by aspecific pattern. By the division, the recognition of an external touchmay be increased and the transparency may be improved. A divided shapeis not particularly limited and may be a straight line, a curved line, azigzag, or the like considering easiness in the manufacturing processand for example, may be shapes shown in FIGS. 22 and 23. A visibilityevaluation result was shown in FIG. 38, when a mesh having a line widthof 15 micrometers and a pitch of 200 micrometers is divided into a linein which each line width is changed up to 5 to 90 and when theconductive wire is placed on the mesh. Further, a visibility evaluationresult was shown in FIG. 39, when a mesh having a line width of 30micrometers and a pitch of 200 micrometers is divided into a line inwhich each line width is changed up to 5 to 90 and when the conductivewire is placed on the mesh. A shade-marked area of the visibilityevaluation result (right) corresponds to an area where a person does noteasily recognize.

The touch screen according to the present invention may be connected toexternal voltage and in this case, may have a structure as shown inFIGS. 24 and 25, but is not particularly limited. An insulating layer ofa PAD part of a wire connected to the external voltage may be removed.

A sheet resistance of the conductive pattern of the touch screenaccording to the present invention may be 200 to 0.001 ohm/square.

A thickness of the conductive pattern of the touch screen according tothe present invention is preferably 10 micrometers or less, morepreferably 300 nm or less, and further more preferably 100 to 300 nm. Aspecific resistance value may be determined according to a kind ofcomposition of the conductive pattern and a sheet resistance value maybe controlled according to a thickness of the conductive pattern. In thepresent invention, by using the method of forming the conductive patternby using the etching resist pattern as a mask as described above, theconductive pattern having a thinner thickness may be acquired ascompared with the case where the conductive pattern is directly printed.

The conductive pattern of the touch screen according to the presentinvention has an aperture ratio of 85% to 98%, a sheet resistance of 1ohm to 200 ohm, a thickness of 100 to 300 nm, and a line width of 0.1 to10 micrometer and satisfies the following equation 1.a/(1−aperture ratio)=A  [Equation 1]

In Equation 1, a is a sheet resistance in a thickness t of a layer madeof a material constituting the conductive pattern and

A is a sheet resistance in a thickness t of the conductive pattern. Theconductive pattern according to the present invention may satisfy thefollowing equations 2 and 3.a/[1−(R−L)² /R ² ]=A  [Equation 2](R−L)² /R ² ×Ts=Tc  [Equation 3]

In Equations 2 and 3, R is a pitch of the conductive pattern, L is aline width of the conductive pattern, a is a sheet resistance in athickness t of a layer made of a material constituting the conductivepattern, A is a sheet resistance in a thickness t of the conductivepattern, Ts is transmittance of the substrate in itself, and Tc istransmittance of the substrate having the conductive pattern.

In this specification, the aperture ratio means a ratio of an area inwhich the conductive pattern is not formed in an overall laminated bodyand the transmittance means a transmission ratio of light shown whenvisible light passes through the substrate.

The conductive pattern of the touch screen according to the presentinvention preferably has a deviation of thicknesses of the conductivepattern within 3% for each position and more preferably within 2%. Theconductive pattern according to the present invention preferably has adeviation of line widths within 30% for each position and morepreferably within 20%. In the present invention, by using the etchingresist pattern as a mask in forming the conductive pattern, thedeviation of the thicknesses and/or the line widths of the conductivepattern may be reduced, as compared with the related art in which theconductive pattern is formed by directly printing the conductive ink andthe paste.

The conductive pattern of the touch screen according to the presentinvention preferably has a pattern form continuously formed in an areaof 7 inch or more and preferably has an area of 10 to 50 inches. Herein,the continuously-formed pattern form means that a connection trace isabsent. In the present invention, by using the over-etching methoddescribed above, the conductive pattern having an ultrafine line widthmay be formed in a large area without the connection trace. Theconductive pattern having the ultrafine line width in the large area isnot implemented by the related art. The connection trace means a tracefor implementing the large area by connecting the conductive patternshaving a small area to each other and for example, the method ofconnecting the conductive patterns in a small area by using a pad partmay be used. In this case, the transmittance is preferably 85% to 98%and the conductivity is preferably 0.1 to 100 ohms. When an electronicapparatus having minimum electrical conductivity and using the same isattached to an electronic device such as a display, they are designnumerical values for preventing the attachment from being significantlyrecognized.

The conductive pattern comprised in the touch screen may be regular orirregular. A pitch of the regular pattern may be several to 2000micrometers, preferably 500 micrometers or less, and more preferably 250micrometers or less. A pitch of the conductive wire pattern of the touchscreen may be smaller than a size of a pixel of a display.

In an exemplary embodiment, the conductive pattern comprised in thetouch screen may be formed by closed figures distributed continuously inan area of 30% or more, preferably 70% or more, and more preferably 90%or more of an overall area of the substrate and may have a shape where aratio of standard deviation for an average value of areas of the closedfigures (a ratio of area distribution) may be 2% or more. As a result, amoire phenomenon may be prevented and excellent electric conductivityand optical properties may be satisfied.

The number of the closed figures may be at least 100.

The ratio of standard deviation for an average value of areas of theclosed figures (a ratio of area distribution) is preferably 2% or more,more preferably 10% or more, and further more preferably 20% or more.

The pattern formed by the closed figures having the ratio of standarddeviation for an average value of areas (a ratio of area distribution)of 2% or more may be 30% or more for the overall area of the substrate.Other shapes of conductive pattern may be at least partially formed onthe surface of the substrate with the conductive pattern.

FIG. 26 exemplifies a conductive pattern of a touch screen according toan exemplary embodiment of the present invention. The ratio of areadistribution of the pattern is 20% or more, for example, 20% to 35%.

In another exemplary embodiment, when the conductive pattern comprisedin the touch screen shows a straight line crossing the conductivepattern in an area of 30% or more, preferably 70% or more, and morepreferably 90% or more of an overall area of the substrate, a ratio ofstandard deviation for an average value of distances between thestraight line and adjacent contact points of the conductive pattern (aratio of distance distribution) may be 2% or more. As a result, a moirephenomenon may be prevented and excellent electric conductivity andoptical properties may be satisfied.

The straight line crossing the conductive pattern may be a line havingminimum standard deviation of distances between the conductive patternand the adjacent contact points. In addition, the straight line crossingthe conductive pattern may be a straight line extending in a verticaldirection to a tangent of any one point of the conductive pattern.

The straight line crossing the conductive pattern may have contactpoints of 80 or more with the conductive pattern.

The ratio of standard deviation for an average value of distancesbetween the straight line crossing the conductive pattern and adjacentcontact points of the conductive pattern (a ratio of distancedistribution) is preferably 2% or more, more preferably 10% or more, andfurther more preferably 20% or more.

The pattern having the ratio of standard deviation for an average valueof distances between the straight line crossing the conductive patternand adjacent contact points of the conductive pattern (a ratio ofdistance distribution) of 2% or more may be formed at an area of 30% ormore for the overall area of the substrate. Other shapes of conductivepattern may be at least partially formed on the surface of the substratewith the conductive pattern.

FIGS. 27 and 28 shows the case where any line is drawn on the conductivepattern. However, the scope of the present invention is not limitedthereto. FIG. 27 shows a one-dimensional form in which conductivepatterns does not cross each other, and FIG. 28 shows a two-dimensionalform in which the electric conductive patterns cross each other andshapes of closed figures are formed on at least some regions. Anotherexample of the conductive pattern is shown in FIG. 29, but the scope ofthe present invention is not limited thereto.

In the touch screen according to the present invention, in order toimplement uniform conductivity and visibility, the aperture ratio of thepattern may be uniform in a unit area. The substrate having theconductive pattern may have transmittance deviation (based on an areawithout artificial pattern disconnection part) of 5% or less which ismeasured at the inside of any circle having a diameter of 0.5 cm in aneffective screen part and at n positions of in the touch screen. In thiscase, local conductivity in the substrate having the conductive patternmay be prevented.

In the present invention, the conductive pattern may be formed bystraight lines, but may be variously modified in curved lines, wavelines, zigzag lines. In addition, at least two of the shaped lines maybe mixed.

According to an exemplary embodiment of the present invention, theconductive pattern may have a boundary shape of figures forming aVoronoi diagram.

In the present invention, the moire phenomenon may be prevented byforming the conductive pattern in the boundary shape of figures forminga Voronoi diagram. The Voronoi diagram is a pattern formed by filling aregion in which a distance between each point and the correspondingpoint is the nearest as compared with a distance from other points whenthe points called a Voronoi diagram generator are disposed at a regionto be filled. For example, when national large-sized retailers aremarked by points and customers visits the nearest large-sized retailer,a pattern marking a business district of each large-sized retailer maybe exemplified. That is, a honeycomb structure in which a space isfilled with regular hexagons and each point of the regular hexagons isselected by the Voronoi diagram generator may form the conductivepattern. In the present invention, when the conductive pattern is formedby using the Voronoi diagram generator, a complicate pattern form whichcan prevent the moire phenomenon generated by interference with otherregular patterns may be easily determined. FIG. 30 exemplifies a patternformation using a Voronoi diagram generator. One example of theconductive pattern is shown in FIGS. 31 to 33, but the scope of thepresent invention is not limited thereto.

In the present invention, the Voronoi diagram generator is regularly orirregularly positioned, such that the pattern derived from the generatormay be used.

Even when the conductive pattern is formed in a boundary shape of thefigures forming the Voronoi diagram, in order to solve the problem onthe visible perception described above, the Voronoi diagram generator isgenerated so that regularity and irregularity are properly controlled.For example, the Voronoi pattern may be prepared by designating apredetermined size of area as a basic unit in an area having the patternand generating points having irregular distribution in the basic unit.Distribution of lines is not concentrated in any one point by using themethod, such that visibility may be complemented.

As described above, in order to implement uniform conductivity andvisibility, when the aperture ratio of the pattern is uniform in theunit area, the number of the Voronoi diagram generators per unit areamay be controlled. In this case, when the number of the Voronoi diagramgenerators per unit area is uniformly controlled, the unit area ispreferably 5 cm² or less and more preferably 1 cm² or less. The numberof the Voronoi diagram generators per unit area is preferably 25 to2,500 numbers/cm² and more preferably 100 to 2,000 numbers/cm².

At least one of the figures forming the pattern in the unit area mayhave a different shape from the rest figures.

According to another exemplary embodiment of the present invention, theconductive pattern may have a boundary shape of figures formed by atleast one triangle forming a Delaunay pattern. In detail, the shape ofthe conductive pattern may be a boundary shape of the triangles formingthe Delaunay pattern, a boundary shape of figures formed by at least twotriangles forming the Delaunay pattern, or a combined shape thereof.

The conductive pattern is formed in the boundary shape of figures formedby at least one triangle forming a Delaunay pattern, such that sideeffect due to diffraction and interference of light may be minimized.The Delaunay pattern is a pattern in which points called Delaunaypattern generators are disposed in a region to fill the pattern andthree adjacent points are connected to one another to draw a triangle,however, when a circumcircle comprising all of edges of the triangle isdrawn, the triangle is drawn so that other points do not exist in thecircumcircle. In order to form the pattern, Delaunay triangulation andcirculation may be repeated based on the Delaunay pattern generator. TheDelaunay triangulation may be preformed by maximizing a minimum angle ofall angles of the triangle to avoid a thin triangle. The concept of theDelaunay pattern was proposed by Boris Delaunay in 1934. An example offorming the Delaunay pattern was shown in FIG. 34. In addition, anexample of the Delaunay pattern was shown in FIGS. 35 to 37. However,the scope of the present invention is not limited just thereto.

In the pattern having the boundary shape of figures formed by at leastone triangle forming a Delaunay pattern, the Delaunay pattern generatorsare regularly or irregularly positioned, such that pattern derived fromthe generators may be used. In the present invention, when theconductive pattern is formed by using the Delaunay pattern generator, acomplicate pattern form which can prevent the moire phenomenon may beeasily determined.

Even when the conductive pattern is formed in the boundary shape offigures formed by at least one triangle forming a Delaunay pattern, inorder to solve the problems on the visible perception and the localconductivity, the Delaunay pattern generator is generated so thatregularity and irregularity are properly controlled. For example, anirregular and uniform reference point is generated in an area insertingthe pattern. In this case, the irregularity mean that a distance betweenthe points is not uniform and the uniformity means that the number ofpoints comprised in the unit area is the same.

The method of generating the irregular and uniform reference points isas described below. As shown in FIG. 45A, any point is generated in anoverall area. Thereafter, an interval between the points is measured andwhen the interval between the points is smaller than a predeterminedvalue, the points are removed. Further, a Delaunay triangle pattern isgenerated based on the points and when the area of the triangle islarger than a predetermined value, the point is added at the inside ofthe triangle. The processes are repetitively preformed to generate theirregular and uniform reference points as shown in FIG. 45B. Thereafter,Delaunay triangles comprising one by one of the generated referencepoints are generated. This step may be performed by using the Delaunaypattern. Distribution of lines is not concentrated at any one point byusing the method, such that visibility may be complemented.

As described above, in order to have uniform conductivity andvisibility, when the aperture ratio of the pattern is uniform in theunit area, the number of the Delaunay pattern generators per unit areamay be controlled. In this case, when the number of the Delaunay patterngenerators per unit area is uniformly controlled, the unit area ispreferably 5 cm² or less and more preferably 1 cm² or less. The numberof the Delaunay pattern generators per unit area is preferably 25 to2,500 numbers/cm² and more preferably 100 to 2,000 numbers/cm².

At least one of the figures forming the pattern in the unit area mayhave a different shape from the rest figures.

According to an exemplary embodiment of the present invention, at leasta part of the conductive pattern may be artificially different from therest pattern. A desired conductive pattern may be acquired by theconstitution. For example, according to the purpose, when some regionsis required to have conductivity higher than the rest area or whenperception of the touch is further sensitively required in some regions,the conductive patterns of the corresponding region and the rest regionsmay vary. In order to have at least a part of the conductive patterndifferent from the rest printing pattern, a line width and a lineinterval of the print pattern may vary. For example, in the case of acapacitive touch screen, whether a portion connected with a side pad hashigh conductivity has been a large issue.

According to an exemplary embodiment of the present invention, theconductor may comprise a region in which the conductive pattern is notformed.

According to an exemplary embodiment of the present invention, theconductive pattern may be blackened. When a paste comprising a metalmaterial is fired at a high temperature, metallic luster is expressed,such that visibility may be deteriorated due to reflection of light. Theproblem may be prevented by blackening the conductive pattern. In orderto blacken the conductive pattern, a blackening material is added into apaste for forming the conductive pattern or the paste is printed andfired, and then blackened to blacken the conductive pattern.

The blackening material added into the paste may be metal oxide, carbonblack, carbon nano-tube, a black pigment, a colored glass frit, or thelike. In this case, composition of the paste preferably comprises aconductive pattern material of 50 to 90 wt %, an organic binder of 1 to20 wt %, a blackening material of 1 to 10 wt %, a glass frit of 0.1 to10 wt %, and a solvent of 1 to 20 wt %.

When blackening after the firing, the composition of the paste maycomprise a conductive pattern material of 50 to 90 wt %, an organicbinder of 1 to 20 wt %, a glass frit of 0.1 to 10 wt %, and a solvent of1 to 20 wt %. The blackening after firing is performed by immersing inan oxide solution, for example, Fe or Cu ion contained solution,immersing in a halogen ion contained solution such as chloride ion,immersing in hydrogen peroxide, nitrate, or the like, and processing byhalogen gas.

In order to maximize an effect for preventing the moire phenomenon, theconductive pattern may be formed so that an area of a pattern havingsymmetric-structure figures is 10% or more for an overall area of thepattern. In addition, an area of the figures, in which at least one oflines which connect a center point of any one figure forming the Voronoidiagram with a center point of adjacent figure forming the border withthe figure has a length different from the rest of the lines, may be 10%or more for an overall area of the conductive pattern. Further, apattern area of the figures, in which at least one side forming a figureformed by at least one triangle forming the Delaunay pattern has alength different from the rest of the sides, may be 10% or more for anarea of the overall conductive pattern.

The moire phenomenon may be avoided by the pattern, but the evasion ofthe moire phenomenon may be maximized by controlling the line width andthe pitch of the conductive pattern. In detail, the conductive patternhas a fine line width of 100 micrometers or less, preferably 0.1 to 30micrometers, more preferably 0.5 to 10 micrometers, and further morepreferably 1 to 5 micrometers, such as all the remaining moirephenomenon can also be prevented. In addition, since the pitch of theconductive wire pattern does not coincide with a size unit of a pixel ofthe display, for example, in the case of a display having a sub pixel of250 micrometers in a longitudinal axial direction, a pitch interval ofthe conductive pattern of 250 pitches is prevented, such that colordistortion of the display due to pixel interference can be prevented.The moire phenomenon according to a line width and a pitch was shown inFIG. 40. As a result of evaluating the moire according to variation inthe line width and the pitch of 10 micrometers or less, in 1.3micrometers, the remaining moire does not occur. Further, in 250pitches, rainbow-color is observed. As a result, a correlation with amajor axial length of a pixel in a display such as an LCD can beverified.

Herein, the present invention is exemplified by the following examples.However, the following examples are to exemplify the present inventionand the scope of the present invention is not limited thereto.

EXAMPLES Example 1

In order to manufacture a touch screen, a glass substrate in which anMoTi alloy with a thickness of 30 nm was deposited on glass of 0.5 t, Cuwith a thickness of 200 nm was deposited thereon again, and Mo with athickness of 30 nm was deposited thereon by using a sputtering processwas manufactured.

Thereafter, etching resist ink (novolak resin composition (Product No.LG412DF made by LG CHEMISTRY, LTD. in KOREA)) was printed by usingCliché having a Voronoi irregular pattern having a size of 8 microns inline width and 200 microns in pitch through reverse offset printing.Thereafter, after a printed sample was baked at 130° C. for 3 minutes,the baked sample was etched (just etching time 30 sec) at 40° C. forapproximately 110 seconds by using Cu etchant (ELCE-100) which is beingprepared by ENF (Korea). Subsequently, the etching resist ink of theVoronoi pattern was removed.

A conductive pattern manufactured thereby was shown in FIG. 41 and theline width of the conductive pattern was 2.65 micrometers. A photographbefore removing the etching resist ink after the etching was shown inFIG. 42 and a photograph of the conductive pattern after removing theetching resist ink was shown in FIG. 43.

Thereafter, a PAD part of an electrode covered with etching resist of aninsulating layer was partially removed using an LGS 100 stripper made byLG CHEMISTRY, LTD.

The process was repeatedly performed with respect to the same metaldeposited on PET having a thickness of 150 microns and thereafter, an(acrylic resin based) adhesive film having a thickness of 100 adhered tothe metal (in this case, an adhesive was removed from an ACF connectionportion in attachment). Therefore, the touch screen was completed byattaching ACF.

Example 2

In order to manufacture a touch screen, a glass substrate in which an Nimetal with a thickness of 20 nm was deposited on glass of 0.5 t, Ag witha thickness of 200 nm was deposited thereon again, and Ni with athickness of 20 nm was again deposited thereon by using the sputteringprocess was manufactured.

Thereafter, UV curable ink (LGP-7 made by NATOKO (Japan) was printed byusing Cliché having the Voronoi irregular pattern having a size of 8microns in line width and 200 microns in pitch through gravure offsetprinting.

Thereafter, after a printed sample was exposed through UV curing ofapproximately 500 mJ/cm², the substrate was baked at 130° C. for 30minutes. Subsequently, the baked substrate was etched (just etching time20 sec) at 40° C. for approximately 60 seconds by using Al etchant (amixed solution of phosphoric acid, nitric acid, acetic acid, and water)which is being prepared by ZEUS (Korea). A conductive patternmanufactured thereby was shown in FIG. 15. Since UV curable ink istransparent, an internal line width could be measured and the line widthof the conductive pattern was 3.74 micrometers and the line width of aninsulating layer pattern was 7.61 micrometers. A photograph of theconductive pattern was shown in FIG. 44.

Thereafter, the PAD part of the electrode covered with the etchingresist of the insulating layer was partially removed by using a KOH 30%solution.

The process was repeatedly performed with respect to the same metaldeposited on PET having a thickness of 150 microns and thereafter, the(acrylic resin based) adhesive film having a thickness of 100 adhered tothe metal (in this case, the adhesive was removed from the ACFconnection portion in attachment). Therefore, the touch screen wascompleted by attaching ACF.

The invention claimed is:
 1. A touch screen, comprising: a substrate; aconductive pattern formed on at least one side of the substrate; and aninsulating layer pattern covering the conductive pattern, wherein thetouch screen is manufactured by the method comprising the steps of: a)forming a conductive layer on a substrate; b) forming an etching resistpattern on the conductive layer; and c) forming a first conductivepattern having a line width smaller than the line width of the etchingresist pattern by over-etching the conductive layer by using the etchingresist pattern, wherein in step c), an etching time of the conductivelayer is just-etching time to a time more extended by 2,000% than thelust-etching time, wherein the conductive pattern has a line width of100 micrometer or less, wherein the conductive pattern has a patternshape formed continuously on an area of 7 inch or more, wherein theinsulating layer pattern has a line width larger than the line width ofthe conductive pattern, and wherein in a cross-section of the line widthdirection of the conductive pattern, a percentage a/b*100 of a distance“a” from one end of the conductive pattern to the insulating layerpattern and a distance “b” from the other end of the conductive patternto the insulating layer pattern is in the range of 90 to
 110. 2. A touchscreen, comprising: a substrate; a conductive pattern formed on at leastone side of the substrate; and an insulating layer pattern covering theconductive pattern, wherein the insulating layer pattern has a taperangle of more than 0 degree to less than 90 degrees, wherein theconductive pattern has a line width of 100 micrometer or less, whereinthe conductive pattern has a pattern shape formed continuously on anarea of 7 inch or more, wherein the insulating layer pattern has a linewidth larger than the line width of the conductive pattern, and whereinin a cross-section of the line width direction of the conductivepattern, a percentage a/b*100 of a distance “a” from one end of theconductive pattern to the insulating layer pattern and a distance “b”from the other end of the conductive pattern to the insulating layerpattern is in the range of 90 to
 110. 3. The touch screen of claim 2,wherein the insulating layer pattern has insulation with a leakagecurrent of 0.1 ampere or less.
 4. The touch screen of claim 2, whereinthe insulating layer pattern comprises at least one selected from thegroup consisting of imide-based polymer, bisphenol-based polymer,epoxy-based polymer, acryl-based polymer, ester-based polymer,novolac-based polymer, and a combination thereof.
 5. The touch screen ofclaim 2, wherein the insulating layer pattern comprises at least oneselected from the group consisting of imide-based monomer,bisphenol-based monomer, epoxy-based monomer, acryl-based monomer,ester-based monomer, a combination thereof, and copolymer thereof.
 6. Atouch screen, comprising: a substrate; a conductive pattern formed on atleast one side of the substrate; and an insulating layer patterncovering the conductive pattern, wherein a taper angle of the insulatinglayer pattern is larger than the taper angle of the conductive pattern,wherein the conductive pattern has a line width of 100 micrometer orless, wherein the conductive pattern has a pattern shape formedcontinuously on an area of 7 inch or more, wherein the insulating layerpattern has a line width larger than the line width of the conductivepattern, and wherein in a cross-section of the line width direction ofthe conductive pattern, a percentage a/b*100 of a distance “a” from oneend of the conductive pattern to the insulating layer pattern and adistance “b” from the other end of the conductive pattern to theinsulating layer pattern is in the range of 90 to
 110. 7. A touchscreen, comprising: a substrate; a conductive pattern formed on at leastone side of the substrate; and an insulating layer pattern covering theconductive pattern, wherein a void is comprised between the conductivepattern and the insulating layer pattern, wherein the conductive patternhas a line width of 100 micrometer or less, wherein the conductivepattern has a pattern shape formed continuously on an area of 7 inch ormore, wherein the insulating layer pattern has a line width larger thanthe line width of the conductive pattern, and wherein in a cross-sectionof the line width direction of the conductive pattern, a percentagea/b*100 of a distance “a” from one end of the conductive pattern to theinsulating layer pattern and a distance “b” from the other end of theconductive pattern to the insulating layer pattern is in the range of 90to
 110. 8. A touch screen, comprising: a substrate; and a conductivepattern formed on at least one side of the substrate and having a linewidth of 100 micrometer or less, wherein the touch screen furthercomprises an insulating layer pattern formed on the conductive pattern,and the insulating layer pattern covers the conductive pattern or has aline width larger than the line width of the conductive pattern, whereinthe conductive pattern has a pattern shape formed continuously on anarea of 7 inch or more, and wherein in a cross-section of the line widthdirection of the conductive pattern, a percentage a/b*100 of a distance“a” from one end of the conductive pattern to the insulating layerpattern and a distance “b” from the other end of the conductive patternto the insulating layer pattern is in the range of 90 to
 110. 9. Thetouch screen of claim 8, wherein the conductive pattern has a taperangle of more than 0 degree to less than 90 degrees.
 10. The touchscreen of claim 8, wherein the insulating layer pattern has a taperangle of more than 0 degree to less than 90 degrees.
 11. The touchscreen of claim 8, wherein a taper angle of the insulating layer patternis larger than the taper angle of the conductive pattern.
 12. The touchscreen of claim 8, wherein a void is comprised between the conductivepattern and the insulating layer pattern.
 13. The touch screen of claim8, wherein the conductive pattern has a sheet resistance of 100ohm/square to 0.001 ohm/square.
 14. The touch screen of claim 8, whereinthe conductive pattern has a thickness of 300 nm or less.
 15. The touchscreen of claim 8, wherein the conductive pattern has an aperture ratioof 85% to 98%, a sheet resistance of 1 ohm/square to 200 ohm/square, athickness of 100 to 300 nm, and a line width of 0.1 to 10 micrometer andsatisfies the following equation 1:a/(1−aperture ratio)=A  [Equation 1] in Equation 1, a is a sheetresistance in a thickness t of a layer made of a material constitutingthe conductive pattern and A is a sheet resistance in a thickness t ofthe conductive pattern.
 16. The touch screen of claim 8, wherein theconductive pattern satisfies the following equations 2 and 3:a/[1−(R−L)² /R ² ]=A  [Equation 2](R−L)² /R ² ×Ts=Tc  [Equation 3] in Equations 2 and 3, R is a pitch ofthe conductive pattern, L is a line width of the conductive pattern, ais a sheet resistance in a thickness t of a layer made of a materialconstituting the conductive pattern, A is a sheet resistance in athickness t of the conductive pattern, Ts is transmittance of thesubstrate in itself, and Tc is transmittance of the substrate having theconductive pattern.
 17. The touch screen of claim 8, wherein theconductive pattern has a deviation of a thickness within 3% for eachposition.
 18. The touch screen of claim 8, wherein the conductivepattern has a deviation of a line width within 30% for each position.